In bone regenerative medicine, scaffolds play a pivotal role in promoting cell adhesion, proliferation, and differentiation. Among the various materials employed for creating scaffolds, mixed materials composed of poly-l-lactic acid and hydroxyapatite (PLLA/HA) have emerged as a favored option owing to their biodegradability, biocompatibility, and ability to support cellular activities. Our research has delved into the optimization of PLLA/HA scaffold design, with a particular focus on pore size, as it significantly influenced cellular behavior. We have found that PLLA/HA scaffolds with the pore size of 400 µm, created using selective laser sintering, exhibited the most favorable conditions for cell adhesion, proliferation, and osteogenic differentiation. Additionally, flow field environment simulation showed that scaffolds with the pore size of 400 µm possessed a more balanced flow field distribution, which was beneficial to cells. This finding provides research support for the pore size selection of bone scaffold in advanced treatment strategies for bone tissue engineering.
Impact Statement
These findings point to poly-L-lactic acid/hydroxyapatite (PLLA/HA) materials as alternatives to traditional titanium alloy for bone reconstruction, aiming to promote cell ingrowth. The biocompatible PLLA/HA composite matches the target tissue’s mechanical stability, reducing scaffold degradation mismatch and minimizing inflammation at the implantation site. Using PLLA/HA scaffolds with optimized pore sizes (e.g., 400 µm) may create a balanced flow field—supporting fluid shear force, nutrient delivery, and metabolite excretion. These aids seed cell survival, enhance cell interactions, and guide tissue-specific differentiation. These synergies could improve functional outcomes and patient recovery, offering insights for advanced orthopedic and regenerative biomaterials.
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